200 Harry Lewis Wieman. 



It is assumed that in botii species the odd body represents two 

 conjugated somatic chromosomes. 



There is much evidence to show that the spireme is formed in 

 the post-telophase stages of the last pre-maturation division by 

 the arrangement of the chromosomes into two parental series 

 which become closely applied to each other (parasynapsis) pro- 

 pucing in this way the double spireme characteristic of synizesis. 



The evidence from observation does not justify the view that 

 the chromosomes are independant individual units of a lower 

 order than the cell. On the other hand, they are to be regarded 

 as permanent cell structures in so far as they express a definite 

 organization of the protoplasm. During amitosis this organiza- 

 tion is assumed to persist, although the chromosomes which repre- 

 sent it in mitosis do not come to expression. This is believed to 

 be due to differences in cell metabolism in the two cases. 



Accepted by The Wistar Institute of Anatomy and Biology, February 10, 1910. Printed August 3, 1910. 



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